Community or block mother kids in the area look up to or go to when there mother or parents are not around. An informal babysitter. Generally resides at the house most popular to the neighborhood. Often found to be giving advise and words of encouragement to the children on the block.

My parents will be home late from work. I'll go to mama dukes for dinner.

Mama duke said I should stay away from the trouble makers down the street.

The Urban Dictionary T-Shirt

An underage teens mom who lets his or her friends get drunk and do drugs in her house, sometimes engaging in drinking and drugging with the kids. The "cool" mom. Not to be confused with a MILF, although sometimes can be.

Jane: Mary, this is my mom.
Mary: Hey mamadukes, where's the booze.
Mamadukes: In the basement with the crack and PCP..Just don't tell your parents.
Mary and Jane: XD